Aim: To study the association between APOE polymorphisms and cerebral infarction through a case-control study among the Chinese Han population.
Methods: First-ever cerebral infarction patients (n=226) whose ages ranged from 40 to 60 years old were recruited from Department of Neurology, Zhongshan Hospital, Shanghai, and Zhejiang Chinese Traditional Medicine Hospital, Zhejiang, China. Unrelated healthy controls (n=201) were selected from the general population in the same area with similar age and sex distribution. APOE was amplified by one-stage PCR using the forward primer: 5'-GGC ACG GCT GTC CAA GGA GCT-3' and reverse primer: 5'-GAT GGC GCT GAG GCC GCG CT-3'. The PCR product was digested directly with 5 U of CfoI and separated by a 20 % polyacrylamide (acrylamide: bis-acrylamide=29:1) nondenaturing gel.
Results: Both cerebral infarction patient and control groups were in Hardy-Weinberg equilibrium. The allele frequency of APOE*2, APOE*3, and APOE*4 was 4.6 %, 81.9 %, and 13.5 % respectively in the patients with cerebral infarction; 5.7 %, 87.3 %, and 7.0 % respectively in the healthy control group. Compared with APOE3/3 subjects, APOE4/4 carriers had a 2.1-fold risk of cerebral infarction (odds ratio 2.1, 95 % confidence limits 1.3 to 3.4). The allele frequency of APOE*4 in the cerebral infarction patient group was significantly higher than that in the control group (13.5 % vs 7.0 %; P=0.002).
Conclusion: APOE 4 is a risk factor for cerebral infarction among the Chinese Han population.